3GPP (3rd Generation Partnership Project) mobile communication systems based on WCDMA (Wideband Code Division Multiple Access) radio access technology are widely developed worldwide. HSDPA (High Speed Downlink Packet Access) which can be defined as the first evolution step of WCDMA provides a wireless access technique having high competitiveness in mid-term future to 3GPP. However, new technology evolution in 3GPP is required in order to continuously maintain competitiveness because requirements and expectations of users and wireless operators continuously increase and competing radio access techniques are continuously developed. The requirements include a reduction in the cost per bit, service availability increase, flexible use of frequency bands, simple structures and open interfaces, appropriate power consumption of terminals, etc.
One of systems, which is considered as a system following third-generation systems, is an OFDM (Orthogonal Frequency Division Multiplexing) system which can attenuate inter-symbol interference with low complexity. OFDM transforms serial input data symbols into N parallel data symbols, respectively loads the N parallel data symbols on N subcarriers and transmit the N subcarriers. Subcarriers maintain orthogonality in the frequency dimension. Each orthogonal channel undergoes independent frequency selective fading and the intervals between transmitted symbols become long, and thus inter-symbol interference can be minimized.
Furthermore, IEEE (Institute of Electrical and Electronics Engineers) 802.16 standard provides techniques and protocols for supporting broadband wireless access. Standardization was performed since 1999 and IEEE 802.16-2001 was approved in 2001. The IEEE 802.16 standard is based on a single carrier physical layer referred to as ‘WirelessMAN-SC’. Then, ‘WirelessMAN-OFDM’ and ‘WirelessMAN-OFDMA’ were added to the physical layer including ‘WirelessMAN-SC’ in IEEE 802.16a standard approved in 2003. IEEE 802.16-2004 standard revised after IEEE 802.16a standard was approved in 2004. IEEE 802.16-2004/Cor1 (referred to as IEEE 802.16e) in the form of ‘corrigendum’ was completed in 2005 in order to correct bug and error of IEEE 802.16-2004.
Recently, multiple-antenna systems have received attention for maximizing the performance and communication capacity of wireless communication systems. The multiple-antenna systems may include MIMO (Multiple Input Multiple Output) system, MISO (Multiple Input Single Output) system and SIMO (Single Input Multiple Output) system. Multiple-antenna techniques can improve transmitted/received data transmission efficiency by adopting multiple transmission antennas and/or multiple receiving antennas instead of a single transmission antenna and a single receiving antenna.